The present invention relates to a sleeve member, notably to a sleeve member adapted for use as in interface between the surfaces of a male and female joint assembly.
Glass laboratory apparatus is conventionally provided with jointing means whereby any desired configuration of apparatus may be made up from constituent individual components. The joint means usually takes the form of a tapered socket or female part on one component and a corresponding tapered male part on another component which is push fitted into the female part, the internal surface of the taper on the female part and the external surface on the male part being accurately ground to ensure uniform mating surfaces which give a good fit between the two parts. This type of joint is termed a male/female push fit type joint herein. However, this form of joint often locks when assembled with the resultant risk of breakage during dismantling. In order to overcome this problem, a coating of grease has been applied to the contacting surfaces of the joint. However, this may lead to grease contamination of the materials flowing through the joint and this is especially true when the joint is subjected to vacuum, raised temperature and/or solvents. As an alternative it has been proposed to provide an interfacing sleeve of a plastic material, such as polytetrafluoroethylene, between the ground surfaces of the male and female parts. However, whilst such sleeves enable an assembled joint to be dismantled with comparative ease, they are difficult to remove from the joint members and are often distorted during removal. Furthermore, such a sleeve does not achieve a seal which is effective at high vacuum.